Filament feed stops during print and printer continues  

RE: Filament feed stops during print and printer continues

One place I would check right away is the heater to the nozzle. The wiring may be intermittent and disconnect when it gets hot. Something could  be loose with the connections.

Tom

RE: Filament feed stops during print and printer continues

A few other things to check for:

• Is the hotend fan spinning the whole time? If that stops at all you could definitely get some heat creep.
• Is the filament path unrestrained? If the increased Z height puts a weird bend or strain on the filament path, the Nextruder may not be able to pull it in as easily.
• Does the Nextruder gear grind a crescent shape into the filament after it stops extruding? If it does not, the idler may need to be tightened to apply more tension on the filament. See last paragraph in this post for an additional check on this same idea.
• Does the print have any defining features at or around the layers near the issue? Perhaps the print is suddenly taking more or less time to print and is printing faster or slower which could result in a clog or the filament grinding.

I'll post again if I can think of some more things to check.

Lastly, this is a long shot since you only recently completed the upgrade, but check the filament idler. Except for your bend in the filament, I had a similar issue where the first layers were fine but as it got more than a couple millimeters up it stopped extruding. Turns out, the idler had warped and was essentially no longer applying tension to the filament. As the first (mostly solid) layers finished, printing speed increased and was consuming filament faster. At some point the hotend just wasn't heating filament fast enough and the very loose idler wasn't apply enough tension to the filament to push the now not-quite-warm-enough-to-melt filament into the nozzle. That resulted in a clog which prevented any filament from moving and then it stopped extruding. Check this Reddit post for a photo and some other details/comments. Again, a long shot but worth checking.

RE: Filament feed stops during print and printer continues

I was looking through the forum to see if I can find an answer to my problem and this is the closest I've come.

I'm having the same problem, but only when I have ironing turned on.  Otherwise, it works fine.  I'm using Jessie PLA filament and PrusaSlicer and default settings.  Anyone have any ideas?

Mike

RE: Filament feed stops during print and printer continues

Thanks for the advice and comments!
I didn’t have a lot of time the last few months to  put my printer to work, but lately did some larger projects using different filaments and types. Very soon the problem happened again. I checked everything that was suggested and had taken special care to control ambient temperature (printer is in an enclosure) to ensure it didn’t get to warm, so I’m fairly sure that was under control too. However, I noticed that when the clog occurred again it was with exactly the same roll of filament it had happened with before. I’ve now take. It out of service and so far everything seems to go ok. It could be that this particular roll of (PLA) filament needs drying. I’m going to do that this week and do some serious printing with it this weekend.

As a side note, I’ve developed a ‘technique’ to clear the nozzle block: I hold the nozzle in a gas flame on the stove holding it with a wrench, and use a 1.5 hex key to push the filament out when it gets hot. Messy, but it works for me! 🙂

RE: Filament feed stops during print and printer continues

I have this issue my self after upgrading to the latest firmware. But mine happens after 40mm above the print bed then it stops feeding filament and acts like all is fine.

RE: Filament feed stops during print and printer continues

For me it happened at different heights so I don't know if the 40mm is significant, but I have printed a lot lately and no more problems. I have since also dried the roll of filament the problem occurred with, and also have upgraded my extruder because of the installation of the MMU3. I've had no problems since. I blame the whole thing on a combination of:

1. Heat creep due to ambient temperature too high in enclosure -> adjust to lower temperature,
2. Brittle (wet) PLA filament due to incorrect storage -> dried PLA and use vacuum bags to store from now on,
3. The feeding mechanism: the filament bends a little when feeding into the nozzle and when it gets stuck it gets grinded by the feeder. The feeder thinks it has moed the filament and the filament sensor detects the filament so the printer happy works on but no filament comes out, then when you stop and try to get the filament out, it breaks. -> I think this got solved when I upgraded the extruder during MMU3 installation

Thomas 

RE: Filament feed stops during print and printer continues

I have found my issue. Thanks to another user on reddit. They were on support with Prusa. He had the same exact issue as I was having. The fix to the issue was to revert to firmware version 5.1.2 do a test print. I did that no print issues at all things worked exactly as planned. Then they instructed to skip the 5.1.3 firmware and instead go to firmware 6.0. I did exactly that and my printer is working as good as new issue is solved. Just wanted to post about the solution incase someone else has this exact problem in the future.